Brake disk for a motorcycle



FIG. 1 is a perspective view of a brake disk for a motorcycle showing my new design;

FIG. 2 is a front view thereof;

FIG. 3 is a back view thereof;

FIG. 4 is a right side view thereof;

FIG. 5 is a left side view thereof;

FIG. 6 is a top plan view thereof;

FIG. 7 is a bottom plan view thereof;

FIG. 8 is a cross-sectional view taken along line 8-8 of FIG. 2;

FIG. 9 is a cross-sectional view taken along line 9-9 of FIG. 2; and,

FIG. 10 is an enlarged view of encircled area 10 in FIG. 4.

The broken lines illustrate environmental structure and form no part of the claimed design. 

The ornamental design for a brake disk for a motorcycle, as shown and described. 